Photography blogger Lau offers a plain-English explanation of two of the most confusing concepts in photography: aperture and focal length. A highlight:

Lenses with larger apertures are faster because, for a given ISO speed, the shutter speed can be made faster for the same exposure. A smaller aperture means that objects can be in focus over a wider range of distance (depth of field).

As someone who has never fully understood this stuff, I consider myself much better informed for having read this. It’s chock full of “Ohhhhhh” information (as in, “Ohhhhhh, that’s what that means.). — Rick Broida